Sample processing in chemical and biologic analyses, such as immunohistochemical (IHC) applications, may require one or a number of various processing sequences or protocols as part of an analysis of one or more samples. The sample processing sequences or protocols may be defined by the individual or organization requesting an analysis, such as a pathologist or histologist of a hospital, and may be further defined by the dictates of a particular analysis to be performed.
The sample processed may be any material, but is most likely a biologic material such as a biological sample or a biological specimen, perhaps such as a histological sample, e.g. tissue and cell specimens, cells, collections of cells, or tissue samples, the definition to include cell lines, proteins and synthetic peptides, tissues, cell preps, cell preparations, blood, bodily fluids, bone marrow, cytology specimens, blood smears, thin layer preparations, and micro arrays. It should also be understood to include slide-based biological samples. In preparation for biologic sample analysis, for example, a biological sample may be acquired by known sample acquisition techniques and may comprise, for example in immunohistochemistry (IHC) applications, tissues generally or even in some applications one or a plurality of isolated cells, such as in microarray samples, and may be presented on a sample carrier such as a microscope slide. Furthermore, the sample may be presented on the carrier variously and potentially in some form of preservation. As one example, a sample such as a layer or slice of tissue may be preserved in formaldehyde and presented on a carrier with one or more paraffin or other chemical layers infiltrating the sample.
IHC applications, for example, may require processing sequences or protocols that comprise steps such as deparaffinization, target retrieval, and staining, especially for in-situ hybridization (ISH) techniques. Important for many IHC applications, and many sample processing sequences and protocols, generally, are temperature characteristics associated with the sample, sample carrier, and the processing environment. As but one example, stains such as histochemical reagents are typically used to identify various histological features. The reagents may employ antibodies, for example, that bind to specific proteins of the sample. In many processes, a need can exist for adequate control of processing characteristics such as temperature. In regard to staining, it should be understood that the term staining can reference the end product of the process, by which certain parts of the sample may be stained, i.e. have obtain a different color, either in the optic range or in another electromagnetic range, such as ultra violet. Staining may be detectable, perhaps automatically detectable, through some change in properties, such as fluorescent properties, magnetic properties, electrical properties or radioactive properties. Staining a sample can involve a series of treatment steps, such as washing, binding of reagents to the specific parts of the sample, activation of the reagents, etc. Sample processing with the reagents may require the addition and removal of reagents in accordance with a defined protocol that may include a defined temperature.
Traditional sample processing technology has provided temperature control through heating devices that heat an entire set of sample carriers in the sampling processing system. Other technologies, such as the sample processing system described in U.S. Pat. No. 6,183,693, may provide heating devices for individual sample carriers that are individually controlled to heat the slides. However, each of these traditional sample processing systems may lack a desired degree of temperature control or temperature tolerances.
Inadequacies in temperature control of traditional technologies may include uncontrolled cooling. Traditional systems may only provide ambient cooling when the heating devices are off. Ambient cooling is not considered active control and may not meet protocol temperature requirements or may not otherwise be optimal. Although healing and heat control may be features of such systems, controlled cooling of the samples, sample carriers, and processing environments may not always be adequately addressed. Cooling techniques such as hooded fans may be incorporated in some traditional technologies. However, these devices can lack sufficient capabilities of temperature control to meet certain protocol requirements, especially temperature tolerances for samples, sample carriers, reagents, and ambient system temperature.
Traditional systems may even lack temperature control, perhaps as related to temperature tolerances generally, as such tolerances may not be adequately maintained during ambient or other traditional cooling, or during processing sequences or events, generally. In some protocols, for example, the temperature tolerances during non-heating periods may be such that uncontrolled temperature changes may produce undesirable results during the processing sequence. Other IHC processes of the protocol may be adversely affected by uncontrolled temperature changes, the degree of temperature change, and temperature changes outside of preferred tolerances. The lack of temperature control may actually dissuade technologists from employing preferred processing sequences or protocols, especially IHC sequences that may be dependent upon a particular temperature tolerance and the amount of temperature change during a processing sequence.
Certain types of temperature control may not have even been addressed in traditional sample processing system technologies. As previously mentioned, reagents can play a vital role in the staining sequence of many processing protocols. The quality of the reagents, therefore, may be important for adequate sample processing. Reagents, for example, can have a certain shelf life that may be limited if maintained at undesirable temperatures such as the typical ambient temperatures of traditional processing systems and the laboratories housing such systems. Traditional technologies may lack the temperature control needed to optimally preserve the reagents stored in the processing system that are often subject to inadequate or changing ambient temperatures of such systems and the laboratory environment.
Previously, in some traditional processing sequences, protocol steps may have been performed manually, potentially creating a time-intensive protocol and necessitating personnel to be actively involved in the sample processing. Attempts have been previously made to automate sample processing to address the need for expedient sample processing and a less manually burdensome operation. However, such previous efforts may have not fully addressed the needs for an automated sample processing system. Previous efforts to automate sample processing may be especially deficient in several aspects that prevent more robust automated sample processing, such as: the lack of sufficient temperature control and temperature monitoring associated with sample processing, and the lack of real-time, lack of active, or lack of adaptive temperature control capabilities for multiple sample batch processing. As but one example, the lack of controlled cooling features of traditional systems may require longer wait times for the technologist during processing sequences to allow samples, sample carriers, and ambient temperatures to reach certain protocol temperatures.
The above-mentioned drawbacks or inadequacies of traditional sampling techniques may also be applicable to other chemical and biologic analyses beyond those examples previously described.
Past efforts at automated sample processing for samples presented on carriers such as slides, such as U.S. Pat. No. 6,352,861 and U.S. Pat. No. 5,839,091 have not afforded the various advantages and other combinations of features as presented herein.